The cape has an emote. The cape must be worn in order to perform this emote.

Should a player achieve skill mastery in a second skill after Invention, the Hooded Invention cape will turn into a Hooded Invention cape (t), which is the trimmed version of the original cape. The Hooded Invention cape (t) has a trim.

Talking to Doc gives an option to toggle the appearance of the cape to a retro version, overriding the normal appearance and making it look similar to how the other skill capes did before the 2015 graphical update. Despite it being a new item, the retro cape can be used with a keepsake key.